Impulse timepiece



May 20 1941- w. E. MAXWELL 2,242,655

IMPULSE TIMEPIECE Filed May 19, 1959 2 Sheets-Sheet l May 20, 1941. w. E. MAXWELL IMPULSE TIMEPIECE Filed May 19, 1939 2 Sheets-Sheet 2 Patented May 20,v 14941 IMPULSE TIMEPIECE Weyman E. Maxwell, Springfield, Mass., assignor to The Standard Electric Time Company, Springfield, Mass., a corporation of Massachusetts Application May 19, 1939, Serial No. 274,529

11 Claims.

This invention relates to improvements ln impulse-timepieces (i. e., timepieces having stepby-step movements of their indicating-means), and more especially to means for imparting stepby-step movement to the time-indicating means of impulse-timepiece movements, a group of which are usually Simultaneously operated under the remote control of a master clock or the like common to them all.

One of the objects of the present invention is to provide superior and effective means for operating an impulse-timepiece movement in a smoother, quieter and less complicated manner than has heretofore been accomplished in devices of this character.

Another object of the invention is to provide superior electromagnetically-operated mechanism comprising a relatively-small number of parts of simple and eective form to provide a device of this character which is reliable, accurate and noiseless for transmitting to the hourhand and minute-hand or the like o1' a secondary timepiece the periodic impulses delivered thereto by a master clock or the like.

Another object of this invention is to provide a superior motor-structure of the eddy-current type whereby the rotary eld-effects produced in the rotary armature of said motor-structure by the periodic electrical impulse received from a master clock may be utilized to avoid, in large measure, the use of gearing for transmitting the periodic impulses to the time-indicating means of an impulse-timepiece.

A particular object of the invention is to provide a superior impulse-timepiece movement having a motor-structure of the eddy-current type in which the armature is rotated by the rotary field-effects from a normal "at rest position through a first stage o1' its operating movement; momentarily arrested in a predetermined position at the end of the said first stage" of its operating movement; retained in its arrested position until after the motor-structure is deenergized; and nally rotated through a second stage movement under a rotational-bias set up in the rotary armature during its rst stage movement and operating to return the said armature to its normal at rest position.

With the above and other objects in view, as will appear to those skilled in the art from the present disclosure, this invention includes all features in the said disclosure which are novel over the prior art.

In the accompanying drawings, in which one mode of carrying out the present invention is shown for illustrative purposes:

Fig. l is a view in rear elevation of an impulsetimepiece movement constructed in accordance with the present invention;

Fig. 2 is a top plan view of the same;

Fig. 3 is a view in side elevation thereof with the parts shown in the relative positions due to them immediately prior to the deenergizing of the motor-structure;

Fig. 4 is a view in side elevation similar to Fig. 3, but showing the several parts in their normal at rest positions in the interval between electrical impulses;

Fig. 5 is a perspective View of the magneticallyoperated armature-stop lever;

Fig. 6 is a perspective view of the rotary amiature, detached;

Fig. 7 is a. view in side elevation of a modified form of the invention; and

Fig. 8 is a perspective view of the rotary armature of the embodiment shown in Fig. 7.

In the embodied form of the invention shown in Figs. l to 6 inclusive, of the drawings for purposes of illustration, the movement-frame of the impulse-timepiece movement is generally designated by the reference character I0. The said movement-frame I0 supports an eddy-current motor-structure comprising a field-structure which is generally designated by the reference character I I. Suitably constructed and arranged to be operated electromagnetically by the field-structure I I is a rotary armature, formed of aluminum or other suitable material providing eddy-currents in response to the action of field-magnets as will hereinafter appear, and which is generally designated by the reference character I2.

The rotary armature I2 is rotatable electromagnetically from a predetermined normal at rest position, shown particularly well in Fig. 4, through a first stage of its operating movement, at the end of which it is momentarily arrested by an electromagnetic armature-stop lever which is generally designated by the reference character I3.

The rotary armature I2 before referred to, is provided with means for imparting thereto a rotational-bias, which preferably operates by gravity, to retain the said rotary armature in its predetermined normal at rest position between recurring impulses, in readiness to be again turned by another impulse.

As shown particularly well in Fig. 1, the rotary armature I2 is rigidly carried by an armatureshaft lli which is connected by a suitable drive connection to a centeror minute-arbor i6 of the timepiece as will hereinafter be described.

The movementdranie it* comprises a front movementnplate il, a rear movement-plate I5, and pillars i9 which are interposed :between and rigidly secured to both of the said movementplates ll and .l by screws 20.

The field-structure H includes a U-shaped magnet-yoke 2i which is formed of iron or the like and includes a crossbar 22 by means of which it is rigidly mounted on the rear face of the front movement-plate il and laterally-spaced sidebars 23 and Eil. Rigidly mounted upon the sidebar 23 are two corresponding field-magnets 25- 25, each of which includes an energizing-coil 25 having a of leadewires 2?-2'1 suitably connecting the two field-coils in series to each other to line-wires ila and 2lb leading from a master cloclr (not shown) As shown particularly well in Figs. 3 and Ll, each of the held-magnets 25--25 also includes a pole-piece 25a formed of magnetic material which is secured at one end to the side-bar 23 of the magnet-yoke 2l, each of the said polepieces beinfT provided at its free end with a sub stantially-diametrical slot 2S. The free end of each of the pole-pieces 25 terminates sufficiently short of the side-arm 26 of the magnet-yole 2l to provide a sumcient space to accommodate the before mentioned rotary armature l2.

The diametrical slot 2t in the free end of each pole-piece 25a receives the straight bar-portion 25 of a suitable shading-coil 35 formed of copper or the like, to provide an unshaded salient pole 3l and shaded salient pole 32, the latter being encircled by the said shading-coil 313. According to Figs. 3 and e, the shaded salient poles 32-32 are displaced in a countercloclawise direction with respect to the unshaded salient poles 3 l-l around the peripheral edge-portion of the rotary armature i2. As thus arranged, when the eldmagnets are energized, rotating iieldeiects will result and the rotary armature i2 will be rotated in a counterclockwise direction as viewed in the iigures above referred to, due to the eddy currents formed therein.

As shown particularly well in Figs. l, 3 and 4, a stabilizing-arm 33 is mounted on the outer end of the armature-shaft ill and is secured in position thereon by means oi a set-screw (ifi. Movable radially upon the arm 33 is a weight which may ee secured in any desired adjusted position by means of a set-screw Lt. rIhe said weight imposes on the armature l2 a gravitational-bias which tends te turn the said armature into and to return the same to a predetermined normal at rest position in a manner as will hereinafter The armature l2 is provided with a radially-projecting stop-linger 3'! which is adap ed to be engaged with and released by the armature-stop lever i3, as will presently appear.

For the purpose of momentarily halting the rotational movement of the rotary armature l2 at the end o a first stage movement thereof, the said armature-stop lever i3 is preferably made oi the bent-lever type and comprises a stop-lever E8, an intermediate bearing-loop 35 receiving and turning upon a pivot-pin t carried by the U-shaped magnet-yoke 2l, and a depending resilient limiting-arm lll. An inverted U-shaped leaf-spring carried by the crossbar 22 of the magnet-yoke 2l is interposed betweenY the limiting-arm 4i and said crossbar 22, as is shown particularly well in Figs. 3 and 4.

The said armature-stop lever i3 is preferably formed of soft steel or other non-permanent magnetic material, and is provided at one side adjacent its free end, with a stop-arm 43 terminating in a stop-unger 44 which is adapted to cooperate with the radially-projecting stopfinger 3'1 of the rotary armature It, in a manner as will more fully hereinafter appear. The free end of the stop-lever arm 38 is cur ed rearwardly and downwardly to provide an actuating-arm 45 reaching within the iield of influence of the held-magnets 25-25.

The armatureshaft i4 is journaled in two spaced-apart bearing-arms 68-48 bent rearn wardly from the rear movement-plate i8 and on opposite sides of the vertical-longitudinal plane of the center-arbor i6. Mounted upon the armature-shaft i4, between the respective bearingarms 11B- 48, is a worm 19 which is provided with a hub-portion 5E! secured to the armature-shaft I4 by a set-screw 5I. The hub-portion 50 of the worm is arranged in axial abutment with the left-hand bearing-arm 4S (as viewed in Fi". l), while a collar 52, which is secured to the armature-shaft i4, is in axial abutment with the right-hand bearing-arm 8. Secured to the center-arbor i5, adjacent the rear end thereof, is a worm-gear 53 which is constructed and arrangedto intermesh with the worm 49 for the purpose of transmitting rotational impulses from the rotary armature i2 to the centerarbor I6.

As shown particularly well in Figs. 3 and 4, the center-arbor I6 extends through the front movement-plate Il and carries at its forward end a minute-hand 54. Fastened to the centerarbor I6, adjacent the rear face of the front movement-plate Il, is a minute-pinion 55 which meshes with and drives a dial-wheel 56 secured to a dial-pinion 51 and journaled therewith upon a stud 5S extending rearwardly from the front movement-plate I?. rihe dial-pinion 5l meshes into an hour-wheel 59 interposed between the front movement-plate ll and the minute-pinion 55. rIhe said hour-wheel 59 carries a forwardlyeXtending hour-sleeve dil which carries at its forward end an hour-hand Gl.

For the purpose of making clear the operation of the impulse clock above described and illustrated in Figs. 1 to 6 inclusive, let it be assumed that the parts occupy the positions in which they are shown in Fig. 4, which may be said to be fw, the normal at rest positions, inasmuch as at ture H and the rotary armature l2 will be urged to turn in the direction indicated by the arrow A in 4' at a relativelyslow rate of movement such, for instance, as at the rate of one revolution in five or six seconds, though the rate of;

- turn may be slower or faster as desired. provided only that, in the particular strucaure shown, the said rotary armature l2 completes its single rotational movement in response to a given impulse from the master clock prior to the time when a v succeeding impulse is due from the master clock.

At the same time that the field-magnets -25 are energized and turn the rotary armature I2 as described, the stop-lever I3 will have its actuating-arm 45 attracted by the fieldmagnets 25-25, with the result that the said stop-lever will swing downwardly into the position in which it is shown particularly well in Fig. 3, to thereby interpose its stop-finger 44 in the path of movement of the stop-finger 31 of the rotary armature I2, to momentarily halt the same at the end of what may be aptly termed a first stage movement of its operation.

As the rotary armature I2 is thus brought to a halt at the end of the said rst stage movement of its operation, the radial arm 33, with the Weight carried thereby, occupies the position shown particularly well in Fig, 3, and in this position imposes on the rotary armature a gravitationalor rotational-bias tending to effect a further continued rotational movement of the armature.

When the field-magnets 25-25 are deenergized, the stop-lever I3 is released from the attractive force of the held-magnets 25-25 and is thereupon raised by the pressure of the U-shaped leaf-spring 42 on the limiting-arm 4 I the upward movement of the said stop-lever I3 being arrested by the engagement of the limiting-arm 4| with a stop-pin 4 Ia. This upward movement of the stoplever I3 serves to remove the stop-finger 44 from the path of the stop-finger 31 on the rotary armature I2, which latter is thus released for a second stage rotational movement which is effected by means of the weight 35 which moves downwardly under the action of gravity from the position in which it is shown in Fig. 3 to a position in which it depends from the rotational axis of the rotary armature to gravitationally stabilize the said armature in its normal at rest position, as particularly well shown in Fig. 4.

From the foregoing, it will be apparent that the stop-lever I3 serves to arrest the rotation of the armature I2, after the field-magnets 25-25 have eiected the rst stage rotational movement of the said armature, until the said fieldmagnets are deenergized whereupon the weight 35 effects the further rotation of the armature I2 to thus complete one revolution of the said armature to correctly register the time-indicating means with the indicia on the dial. It will thus be understood that each complete rotation of the rotary armature I2 as above described, will transmit a movement equivalent to one minute of time, to the hour-hand 6I and minute-hand 54 through the worm 49 and worm-gear 53.

The weight 35 during the second stage of rotational movement of the armature I2 as above described, serves to rotate the latter after the release thereof by the stop-lever I3, a degree suiii cient to bring the stop-linger 31 of the said armature out from beneath the stop-finger 44 of the stop-lever I3 to thus insure the rotary armature I2 being free to again be effected for rotation by the field-structure Il, when the latter agam receives an impulse from the master clock for advancing in step-by-step movement the hour-hand 6I and minute-hand 54 one minute of time-indicating distance.

In the modified form of the invention shown 1n Figs. 7 and 8, the movement-frame comprises a front movement-plate 63, a rear movement-plate 64, and spacing-pillars 65. Mounted on and supported by the rear movement-plate 64, is a fieldstructure, generally designated by the reference character 66. The said field-structure 66 is generally similar in construction to that shown in Figs. 1 to 4 inclusive but, as shown particularly well in Fig, 7, is disposed substantially in a vertical plane and spaced rearwardly from the rear movement-plate 64. For this purpose, the eldstructure 66 is supported by a horizontal arm 61 which extends rearwardly from the upper end of a vertical plate 68 secured to the rear movement.- plate 64, The said field-structure 66 includes two corresponding field-magnets 69-69 having energizing-coils provided with lead-wires 10-10 which connect the energizing-coils in series to each other and to line-wires 10a and 18D leading from a master clock (not shown);

As shown in Fig. 7, the pole-piece of each of the field-magnets 69-69 is provided with an unshaded salient pole 1I and a shaded salient pole 12. For this purpose, the straight bar-portion 13a of a shading-coil 13 is mounted in a substantiallydiametrical slot in the pole-piece of each of the field-magnets 69-68 in a manner similar to that in which each of the straight bar-portions 29-28 of the shading-coils 30-30 are mounted, as described in connection with Figs. l to 4 inclusive. A rotary armature 14, which is mounted upon an armature-shaft 15, drives a worm 16 fastened to the said armature-shaft, the said worm 16 being in mesh with a Worm-gear 11 fixed to a centeror minute-arbor 16.

As shown in Fig. '1, the center-arbor 18 extends through the front movement-plate 63 and carries at its forward end a minute-hand 19. Fastened to the center-arbor 18, adjacent the rear face of the front movement-plate 63, is a minute-pinion which meshes with and drives a dial-wheel 8I secured to a dial-pinion 82 and jcurnaled therewith upon a stud 83 extending rearwardly from the front movement-plate 63. The dial-pinion 82 meshes with an hour-wheel 84 interposed between the front movement-plate 63 and the minute-pinion 30. The said hour-wheel 84 carries a forwardly-extending hour-sleeve 85 which carries at its forward end an hour-hand 86.

According to the embodiment shown in Figs. '1 and 8, the rotary armature 14 comprises a composite structure by means of which it is rendered rotationally responsive to the rotary held-effects produced by the periodic impulses from the master clock in the field-structure 66 for imparting thereto its first stage movement; electromagnetically responsive to the eld-magnets 68-69 for the purpose of momentarily arresting the said armature at the end of its first stage of movement; and gravitationally responsive to the force of gravity for turning the said armature through its second stage of movement.

For this purpose, in the embodied form of the invention, the rotary armature 14 which, in the main, is constructed oi' aluminum or other suitable non-magnetic material, has a segmental marginal portion thereof removed to receive a segmental plug 81 of the same size and shape, constructed of magnetic material. The said segmental plug 81 is tted into the segmental opening formed in the outer marginal-portion of the rotary armature 14 and fastened therein in any suitable manner When an impulse from the master clock is received simultaneously by both of the field-magnets ISS- 69, a rotating field-effect will be developed by the field-structure 66, which will turn the rotary armature 14, in the direction of the arrow B to move the magnetic-plug 81 toward the right and upwardly, according to Fig. 7. As the said magnetic-plug Bl passes its upper deadcenter and moves toward the left, according to Fig. 7, it comes into the eld of influence of the field-magnets 653-69 and is ilnally arrested in centralized relation thereto by the lock-in effeet produced by the said field-magnets at the end or" the iirst stage of the armatures operating movement. In other words, the magneticplug 8l is constructed and arranged to momentarily arrest the rotary armature i4 at the end of its rst stage of operating movement and, after each deenergization of the held-magnets {iS-JSS, to impart a rotationaland, in the present instance, a gravitational-bias to the said armature ior moving it through its second stage of operating movement.

For these purposes, the magnetic-plug Sl may be constructed of soit iron or other suitable nonpermanent magnetic material, and is made of suflicient size to secure an effective lock-in efiect with the magnetic field of the held-magnets @S9-85. As thus formed, the magnetic-plug 81 Will also provide sunicient weight to impart the said second stage rotational movement to the said armature from its momentarily-arrested position, at the end or" the rst stage of armature movement, to the end of the latters movement-cycle and into its normal at rest position, as is particularly well shown in Fig. 7.

In its normal at rest position, according to Fig. 7, the magnetic-plug Sl serves to stabilize, in their normal at rest positions, the rotary armature 'M and the time-indicating mechanism connected thereto.

During the first stage movement i each movement-cycle of the rotary armature, the magnetic-plug @l is carried upwardly in a counterclockwise direction (according to Fig. 7) past its upper dead-center until it is disposed in the magnetic field of the field-magnets (iQ- 69, by which it is arrested and with which it is electromagnetically interlocked until the said eldmagnets are deenergized. As soon as this deenergization of the field-magnets occurs, the magnetic-plug l'l serves merely as a weight to impart a rotational-bias to the armature, which latter is thereby moved downwardly through its second stage movement into, and stabilized in, its normal at rest position.

As clearly shown in Fig. 7, the field-structure Gt of the motor-structure is arranged at a distance from the magnetic-plug 8l, in the latters normal at rest position, to render the rotary field-effects on the rotary armature 'i4 predominant over any electromagnetic attraction of the field-magnets *S2- 6d for the said magneticplug 81.

It will be understood from the foregoing that each complete rotation of the rotary armature 14 effects, through the worm 'iii and worm-gear l1, the advancement of the hour-hand 86 and minute-hand l@ one minute of time-indicating distance to thus correctly register the time-indicating means with the indicia on the dial.

The duration of periodic impulses from the master clock need not be prolonged beyond a period surlicient to impart the first stage rotational movement to a quietly-rotating armature. At the completion of the first stage of rotational movement, the said armature is further rotated by a rotational-bias to complete one revolution or the said armature, which turns in synchronism with the time-pointer set of the timepiece and may be connected thereto by a continuous slow-moving gearing, such as wormgearing, which renders the operating-connections self-locking against all but the normal actuatingmovements transmitted by the rotary armature.

The use of a motor-structure of the eddy-current type conduces to the production of a comparatively-inexpensive impulse-timepiece movement which is quiet and reliable in operation and comprises a relatively small number of parts of simple and eiiective form, which may be operated by pulsating or alternating currents of commercial frequencies such, for example, as 25, 50 and 60 cycle currents which may be preferably, reduced to 24 volts.

The invention may be carried out in other specic ways than those herein set forth Without departing from the spirit and essential characteristics of the invention, and the present embodiments are, therefore, to be considered in all respects as illustrative and not restrictive, and all changes coming Within the meaning and equivalency range of the appended claims are intended to be embraced therein.

I claim:

l. An impulse-timepiece movement, comprising: a time-indicator; a field-structure including a field-coil and constructed to be energized by periodic electrical impulses; a rotary armature constructed and arranged to have eddy currents generated therein by the energization of said held-structure and to be periodically rotated through a rst-sta-ge of its operating movement by the electromagnetic reaction between said eddy currents and the said field-structure, the relationship between the said field-structure and the said rotary armature producing an electromagnetic reaction of substantially-constant value during at least the major portion of the energized phase of the said field-structure; means movable in the said first-stage movement of the rotary armature and rendered operative by the deenergization of the said field-structure for additionally rotating the said armature through a second-stage of its movement; and operatingconnections between said rotary armature and said time-indicator.

2. An impulse-timepiece movement, comprising: a time-indicator; a held-structure including a :Field-coil and constructed to be energized by periodic electrical impulses from a remote source and generating rotary eld effects, the said eldstructure being positioned in electrical-influencing relationship with respect to a rotary armature to exert a rotary effect thereon; a rotary armature constructed and arranged to have a rststage of its operating movement periodically imparted thereto by the rotary eld effects, due tothe energization of said held-structure, the said rotary eld eiiects having a substantially-constant value during at least the major portion oi the energized phase of the said field-structure, the said rotary armature having a second-stage of its operating movement imparted thereto by a rotational-bias due to the first-stage of its operating movement; and operating-connections between said rotary armature and the said timeindicator.

3, An impulse-timepiece movement, comprising: a time-indicator, a held-structure including a field-coil and constructed to be energized by periodic electrical impulses; a rotary armature constructed and arranged to have eddy currents generated therein by the energization of said held-structure and to be periodically rotated through a rst-stage of its operating movement by the electromagnetic reaction between the said eddy currents and the said field-structure, the relationship between the said field-structure and the said rotary armature producing an electromagnetic reaction of substantially-constant value during at least the major portion of the energized phase of the said field-structure; means electromagnetically responsive to the said fieldstructure for terminating the said first-stage of the operating movement of said armature; and means rendered operative by the deenergization of the said field-structure for imparting to said armature a second-stage of its operating movement; the said means being constructed to terminate the said second-stage of the armatures movement in a position corresponding to a predetermined position of said time-indicator.

4. An impulse-timepiece movement, comprising: a time-pointer set; a field-structure including a field-coil and constructed to be energized by periodic electrical impulses; a rotary armature constructed and arranged to have eddy currents generated therein by the energization of said field-structure and to be periodically rotationally displaced by electromagnetic reaction between said eddy currents and the said field-structure; means energized by said field-structure for predetermining the extent of and terminating a first-stage movement of the armature from a predetermined at rest position thereof; means carried by and imposing upon said armature a rotational-bias tending to further turn the armature for completing its movement-cycle, said rotational-bias being rendered operative by the deenergization of said field-structure; and operating-connections between said rotary armature and said time-pointer set.

5. A secondary impulse-timepiece having an operating motor-structure of the eddy-current type, the said motor-structure comprising a fieldstructure having shaded and unshaded salient poles and generating rotary eld effects, the said field-structure being positioned in electrical-influencing relationship with respect to a rotary armature to exert a rotary effect thereon; a rotary armature constructed and arranged to be periodically rotated by the rotary field effects produced by said field-structure thereon and provided with a stop-finger; and a magnetic stoplever movable by the energization of the said field-structure into the path of said stop-finger to arrest the armature at the end of a first-stage movement thereof, said rotary armature being provided With means tovimpart thereto, in its arrested position, a gravitational-bias which is rendered operative by the deenergization of the said field-structure to complete the movementcycle of said rotary armature; and operatingconnections to be interposed between the rotary armature and the time-pointer set of the impulsetimepiece.

6. A secondary impulse-timepiece having a motor-structure of the eddy-current type for driving the time-indicator of the timepiece and comprising a field-structure including a eldmagnet provided with shaded and unshaded salient poles and generating rotary field effects, the said field-structure being positioned in electrical-influencing relationship with respect to a rotary armature to exert a rotary effect thereon; a rotary armature constructed and arranged to be periodically turned by the rotary field effects produced by said field-structure and having a stopnnger; a magnetic stop-lever movable into the circular path of the said stop-finger by the energization of the said field-structure to arrest the armature at the end of a first-stage movement thereof from a, predetermined at rest position of said armature; and a weight movable by and imparting to said rotary armature, in its position at the end of its first-stage movement, a rotational-bias for imparting a second-stage movement thereto, said weight being arranged to depend below the axis and in the axial plane of the rotary armature at the end of its said second-stage movement.

'7. A secondary impulse-timepiece movement having a time-indicator and means for transmitting a step-by-step movement thereto, the said movement-transmitting means including a motor of the eddy-current type comprising: a fieldstructure including a field-magnet for receiving periodic electrical impulses from a master clock and generating rotary field effects, the said fieldstructure being positioned in electrical-influencing relationship with respect to a rotary armature to exert a rotary effect thereon; a rotary armature constructed and arranged to be periodically turned by the rotary field effects produced by said field-structure, said rotary armature being provided with a marginal segmental portion constructed of magnetic material arranged to stabilize the rotary armature in a normal at rest position when the said field-structure is deenergized and to impart a rotating-bias to the rotary armature at the end of a first-stage of the armatures operating movement, the said marginal segmental portion of the rotary armature being arranged to terminate the said first-stage movement thereof by its electromagnetic lock-in arrangement with respect to the energized fieldstructure and rendered gravitationally operative by the deenergization of the said field-structure to impart an additional turning movement to the armature to complete a movement-cycle of the same and to stabilize it in its normal at rest position.

8. A secondary impulse-timepiece movement, comprising: a time-pointer set; an actuatingspindle therefor; a motor of the eddy-current type including a field-structure having a fieldmagnet constructed to be energized from a master clock and generating rotary field effects, the said field-structure being positioned in electricalinfluencing relationship with respect to a rotary armature to exert a rotary effect thereon and a rotary armature constructed and arranged to be periodically actuated by the rotary eld effects of said eld-structure; means electromagneticallyresponsive to the energization of said field-structure for arresting the rotary armature at the end of a rst-stage of its operating movement; and means movable in the said first-stage movement of the rotary armature to impart a rotationalbias thereto, the last said means being rendered operative by the deenergization of the said eldstructure to complete the movement-cycle of the rotary armature and to stabilize it in a normal "at rest position corresponding to a predetermined position of the time-pointer set, the said rotary armature being connected to the actuating-spindle for the time-pointer set.

9. A secondary impulse-timepiece movement, comprising: a time-indicator; a field-structure constructed to receive periodic electrical impulses from a master clock and generating rotary field effects, the said field-structure being positioned in electrical-iniiuencing relationship with respect to a rotary armature to exert a rotary effect thereon; a, rotary armature constructed and arranged to be periodically turned by the rotary field effects of said field-structure, through a first stage of its operating movement from a normal at rest position corresponding to a predetermined position of the time-indicator and provided with means movable in the said first stage of its operating movement to impose thereon a rotational-bias tending to effect a second stage rotational movement of the said armature; and means operated by the energization of said field-structure for momentarily arresting the rotational movement of the rotary armature at the end of said rst stage movement thereof and releasable by the deenergization of the eldstructure to effect the said second stage of rotational movement of the rotary armature by the action of said rotational-bias; the said bias-creating means being constructed and arranged to terminate the said second stage movement and to complete an operating-cycle of the rotary armature for each periodic electrical impulse received by the said eldstructure.

.1.0. A secondary impulse-timepiece movement, comprising: a time-indicator; a field-structure constructed to receive periodic electrical impulses from a master clock and generating rotary eldeffects, the said iield-structure being positioned in electrical-influencing relationship with respect to a rotary armature to exert a rotary effect thereon; a rotary armature constructed and arranged to be moved by the rotary field-effects of said held-structure when energized, through a first stage turning movement from a normal at rest position corresponding to a predetermined position of the time-indicator; a Weight movable by the rotary armature and being in eccentric relation to the rotary aXis thereof and arranged to depend in the vertical axial plane of the rotary armature in the said normal at rest position thereof; means operated by the energization of said eld-structure for momentarily arresting the rotational movement of the rotary armature after the eccentrically-mounted Weight has been raised to and moved past the upper dead center of its movement into a position in which, at the end of the said rst stage movement of the rotary armature, it imparts a rotational-bias to the rotary armature, the said armature being released by the deenergization of the eld-structure to effect a second stage rotational movement thereof under the action of said rotational-bias, the arrangement of the said eccentrically-mounted weight being adapted to terminate the said second stage movement thereof in the normal at rest position of the said rotary armature.

11. A secondary impulse-timepiece movement, comprising: a time-indicator; a held-structure constructed to receive periodic electrical impulses from a master clock and generating rotary eld eiT-ects, the said field-structure being positioned in electrical-inuencing relationship with respect to a rotary armature to exert a rotary effect thereon; -a rotary armature constructed and arranged to be periodically moved by the rotary field effects of the field-structure through a rst stage rotational movement from a normal at rest position corresponding to a predetermined position of the time-indicator; a magnetic-plug carried by the rotary armature and arranged to be electromagnetically locked with the said field-structure for momentarily arresting the rotary armature at the end of its said rst stage operating movement and to impart a gravitational-bias tending to effect a second stage of the operating movement of the rotary armature, said rotary armature being released by the deenergization of the said eld-structure to effect the said second stage of its operating movement.

y WEYMAN E. MAXWELL. 

